The Arab states of the Gulf region have agreed to launch a single currency modelled on the euro, hoping to blaze a trail towards a pan-Arab monetary union swelling to the ancient borders of the Ummayad Caliphate.

The move will give the hyper-rich club of oil exporters a petro-currency of their own, greatly increasing their influence in the global exchange and capital markets and potentially displacing the US dollar as the pricing currency for oil contracts. Between them they amount to regional superpower with a GDP of $1.2 trillion (£739bn), some 40pc of the world’s proven oil reserves, and financial clout equal to that of China.

Saudi Arabia, Kuwait, Bahrain, and Qatar are to launch the first phase next year, creating a Gulf Monetary Council that will evolve quickly into a full-fledged central bank.